Techniques for managing a plurality of radio access technologies accessing a shared radio frequency spectrum band

• US 10,419,157 B2
• Filed: 03/06/2018
• Issued: 09/17/2019
• Est. Priority Date: 02/11/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Yerramalli, Srinivas, Luo, Tao, Damnjanovic, Aleksandar, Papaleo, Marco, Malik, Rahul, Gaal, Peter
• Primary Examiner(s): Ho, Duc C
• Application Number:
  US15/913,739
• Publication Number:
  US 20180198556A1
• Time in Patent Office: 560 Days
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Techniques are described for wireless communication. A first method includes sensing an indication of first radio access technology (RAT) communications occupying a shared radio frequency spectrum band; and configuring, in response to the sensing, at least one parameter of a second RAT used by a device to contend for access to the band. A second method includes randomly selecting a number from a range of numbers extending between a lower bound and an upper bound; contending for access to a shared radio frequency spectrum band by performing an extended clear channel assessment (ECCA) procedure over a plurality of CCA slots, the plurality of CCA slots including a first number of CCA slots equal to the upper bound; and winning contention for access to the band after determining, while performing the ECCA procedure, that the band is available for a second number of CCA slots equal to the randomly selected number.

Claims

1. A method for wireless communication, comprising:

determining, by a first device associated with a first radio access technology (RAT), that a shared radio frequency spectrum is shared with a second device of a second RAT;

determining, based at least in part on the determination that the shared radio frequency spectrum is shared, an energy detection threshold for a clear channel assessment (CCA);

identifying a number of CCA slots for which the shared radio frequency spectrum is available before the first device accesses the shared radio frequency spectrum; and

performing the CCA using the determined energy detection threshold and the identified number of CCA slots.

2. The method of claim 1, wherein determining the energy detection threshold comprises:

determining the energy detection threshold to be a first energy detection threshold based at least in part on determining that the shared radio frequency spectrum is shared with the second device of the second RAT, and wherein the first energy detection threshold is higher than a second energy detection threshold, the second energy detection threshold based at least in part on the shared radio frequency spectrum being available.

3. The method of claim 1, wherein the first RAT comprises a cellular RAT and the second RAT comprises a Wi-Fi RAT.

4. The method of claim 1, wherein the CCA is performed using the determined energy detection threshold to detect transmissions associated with the first RAT and the second RAT.

5. The method of claim 1, wherein the identified number of CCA slots is a last number of the CCA slots in which the CCA is performed when the first device has not accessed the shared radio frequency spectrum.

6. The method of claim 1, wherein determining the energy detection threshold:

determining the energy detection threshold for at least one CCA slot.

7. The method of claim 6, further comprising:

performing a number of CCAs based at least in part on the determined energy detection threshold, wherein the number of CCAs are performed in a set of CCA slots.

8. The method of claim 1, further comprising:

configuring the first device to determine the energy level of the shared radio frequency spectrum following a period in which the shared radio frequency spectrum is shared.

9. The method of claim 1, further comprising:

configuring a range of numbers from which a random number is selected, wherein the random number determines a number of CCA slots over which the first device performs at least one of a plurality of extended CCAs.

10. The method of claim 9, wherein configuring the range of numbers comprises at least one of:

increasing a lower bound of the range of numbers, or increasing an upper bound of the range of numbers, or a combination thereof.

11. The method of claim 10, further comprising:

increasing a duration of a last CCA slot of the random number of CCA slots in which the at least one of the plurality of extended CCAs is performed.

12. The method of claim 11, wherein the plurality of extended CCAs comprises a first extended CCA followed by a second extended CCA.

13. The method of claim 12, wherein the first extended CCA is configured to be performed over a first number of CCA slots and the second extended CCA is configured to be performed over a second number of CCA slots.

14. The method of claim 1, further comprising:

configuring a deferment period for the first device to wait, upon determining that the shared radio frequency spectrum is shared, before performing an additional number of CCAs; and

configuring the first device to win contention for access to the shared radio frequency spectrum upon determining the shared radio frequency spectrum is available for each of the additional number of CCAs.

15. The method of claim 1, wherein:

determining that the shared radio frequency spectrum is shared is based at least in part on a number of transmitters detected within an energy detection range of the first device.

16. The method of claim 1, wherein:

determining that the shared radio frequency spectrum is shared is based at least in part on a failure rate of transmissions for which feedback is reported.

17. The method of claim 1, wherein:

determining that the shared radio frequency spectrum is shared is based at least in part on an erasure rate for transmissions for which an error is not reported.

18. The method of claim 1, wherein:

determining that the shared radio frequency spectrum is shared is based at least in part on a variance between a supported modulation and coding scheme (MCS) and an MCS actually used.

19. The method of claim 1, wherein the first device comprises one of a base station or a user equipment (UE), and wherein the respective one of the base station or the UE determines the energy detection threshold and performs the CCA.

20. An apparatus for wireless communication, comprising:

a processor,

memory coupled to the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to;

determine, by a first device associated with a first radio access technology (RAT), that a shared radio frequency spectrum is shared with a second device of a second RAT;

determine, based at least in part on the determination that the shared radio frequency spectrum is shared, an energy detection threshold for a clear channel assessment (CCA);

identify a number of CCA slots for which the shared radio frequency spectrum is available before the first device accesses the shared radio frequency spectrum; and

perform the CCA using the determined energy detection threshold and the identified number of CCA slots.

21. The apparatus of claim 20, wherein the instructions to determine the energy detection threshold are executable by the processor to cause the apparatus to:

determine the energy detection threshold to be a first energy detection threshold based at least in part on determining that the shared radio frequency spectrum is shared with the second device of the second RAT, and wherein the first energy detection threshold is higher than a second energy detection threshold, the second energy detection threshold based at least in part on the shared radio frequency spectrum being available.

22. The apparatus of claim 20, wherein the first RAT comprises a cellular RAT and the second RAT comprises a Wi-Fi RAT.

23. The apparatus of claim 20, wherein the identified number of CCA slots is a last number of the CCA slots in which the CCA is performed when the first device has not accessed the shared radio frequency spectrum.

24. The apparatus of claim 20, wherein determining the energy detection threshold determining the energy detection threshold for at least one CCA slot.

25. The apparatus of claim 20, wherein the instructions are further executable by the processor to cause the apparatus to:

configure the first device to determine the energy level of the shared radio frequency spectrum following a period in which the shared radio frequency spectrum is shared; and

perform a number of CCAs based at least in part on the determined energy detection threshold, wherein the number of CCAs are performed in a set of CCA slots.

26. The apparatus of claim 20, wherein determining that the shared radio frequency spectrum is shared is based at least in part on:

a number of transmitters detected within an energy detection range of the first device, a failure rate of transmissions for which feedback is reported, an erasure rate for transmissions for which an error is not reported, a variance between a supported modulation and coding scheme (MCS) and an MCS actually used, or a combination thereof.

27. An apparatus for wireless communication, comprising:

means for determining, by a first device associated with a first radio access technology (RAT), that a shared radio frequency spectrum is shared with a second device of a second RAT;

means for determining, based at least in part on the determination that the shared radio frequency spectrum is shared, an energy detection threshold for a clear channel assessment (CCA);

means for identifying a number of CCA slots for which the shared radio frequency spectrum is available before the first device accesses the shared radio frequency spectrum; and

means for performing the CCA using the determined energy detection threshold and the identified number of CCA slots.

28. A non-transitory computer readable medium storing code for wireless communication, the code comprising instructions executable by a processor to:

determine, by a first device associated with a first radio access technology (RAT), that a shared radio frequency spectrum is shared with a second device of a second RAT;

determine, based at least in part on the determination that the shared radio frequency spectrum is shared, an energy detection threshold for a clear channel assessment (CCA);

identify a number of CCA slots for which the shared radio frequency spectrum is available before the first device accesses the shared radio frequency spectrum; and

perform the CCA using the determined energy detection threshold and the identified number of CCA slots.